Coulter mounting



Nov. 19, 1968 R. G. MOE

COULTER MOUNTING Filed Aug. 31, 1966 n /M P @110 i :W Q /WMM United States Patent 3,411,589 COULTER MOUNTING Richard G. Moe, New Berlin, Wis., assignor to Allis-Chalmers Manufacturing Company, Milwaukee, Wis. Filed Aug. 31, 1966, Ser. No. 576,346 8 Claims. (Cl. 172-572) The present invention relates to plows and more particularly to coulters for plows and which are adapted to yield to prevent damage when they encounter obstructions, and an object of the invention is to generally improve the construction and operation of devices of this class.

A coulter, which commonly comprises a plane circular disc having a sharp edge and mounted to roll along the ground in advance of a plow bottom to cut the surface trash and make the initial opening in the ground, is vulnerable to damage when striking rocks and the like in stony soil. Such coulters have been mounted in the past on swinging arms which are spring loaded so that the coulters may rise and pass over stones and the like without damage. Coulters, however, take a substantial amount of punishment during ordinary operation and which may result in premature excessive Wear, looseness of the mounting, tipping of the coulter disc to one side and possible damage to the spring in the event of severe impact with an obstruction. Such looseness may affect the depth at which the coulter will run and in other ways result in unsatisfactory performance.

It is the principal object of the invention to provide a device which will eliminate these difiiculties.

More particularly, it is an object to provide a coulter mounting which will support and guide the coulter accurately in its desired position through the use of a swinging arm having a bearing of such a nature that it will function over long periods with no appreciable wear, in which any end-play is taken up by double use of the spring which normally holds the coulter down to its work, in which the down position of the arm is positively determined by parts of the structure, and which is provided with stop means to prevent excessive upward swinging of the arm which might damage the spring.

Further objects and advantages will become apparent from the following description and accompanying drawings, in which:

FIG. 1 is a plan view with parts broken away of a coulter construction embodying the invention;

FIG. 2 is a left side elevation of the same with parts broken away.

As seen in the drawings, the device includes a disc 10 which rotates on a suitable or well known type of bearing 12 carried on an arm 14 which is swingable up and down on a bearing generally designated as 16, which will later be described and which forms part of a pivot casting 18. Pivot casting 18 is journaled on a shank 20, which is adjustably fixed on a plow frame (not shown) in well known manner and having a vertical or substantially vertical journal portion 22. Pivot casting 18 is retained on journal portion 22 by means of a transverse pin 24.

The ground reaction on disc 10 is upward, tending to raise casting 18, and a collar 26 is fixed on journal portion 22 as by means of a set screw 28 and against which cast- I ice of travel or rolling of disc 10 and which has fixed concentrically with bore 38 a shaft or pintle 40 so as to provide a clearance space between the outer surface of pintle 40 and the inner surface of bore 38. A sleeve 42 of a thickness to substantially exactly fill the clearance between pintle 40 and bore 38 is disposed in said clearance space projecting beyond the outer margin of casting 18 and being fixed in relation to above mentioned arm 14 so as to serve as a shank or hinge pin for the latter about and with which it can swing.

It will be noted that sleeve 42 is quite rugged and of generous dimensions so as to positively guide the swinging movement of arm 14 accurately about the axis of sleeve 42 and incidentally about the axis of pintle 40. Sleeve 42 has a bearing surface on its inner face on pintle 40 and also on its outer face in bore 38 so that an extremely large amount of bearing surface is presented between the several parts. In this way arm 14 is very accurately guided in its swinging movement and prevented from deviating in any manner from its predetermined relation to casting 18 except for the desired up and down swinging movement. Disc 10 is therefore maintained in correct relation to the ground, and over long periods of use the amount of wear which takes place on sleeve 42 is insignificant.

Pintle 40 extends through sleeve 42 outwardly of arm 14 and has disposed thereabout a spiral spring 44. Spring 44 has an outer anchorage or hook portion 46 engaged with a pin 48 fixed in pintle 40, and at its other end it has a finger portion 50 extending alongside arm 14, spring 44 being so biased as to continually press downwardly as seen in FIG. 2, against a pin 52 fixed in arm 14. The reaction of spring 44 would tend to turn pintle 40 in the opposite direction or counterclockwise as seen in FIG. 2, and this is prevented by means of a pin 54 engaged with casting 18 and pintle 40 inwardly beyond the margin of bore 38.

Spring 44 is also biased in such a manner that finger 50 presses inwardly against arm 14 and would take a position approximately as shown in broken lines in FIG. 1 if not prevented by arm 14. Inward pressure is thereby continuously exerted against arm 14 and sleeve 42 and which maintains the inner end of sleeve 42 in thrust bearing relation to a shoulder 56 formed at the inner end of bore 38. In this way all end-play is removed from sleeve 42, and any slight looseness which may develop is auto matically taken up by the pressure of spring 44.

Pin 52 extends entirely through arm 14 and on the side opposite to finger 50 engages a stop lug 58 on casting 18, which establishes a lowermost position thereof and of arm 14. This is the working position of the coulter; and if the latter is raised by contact with an obstruction so as to flex spring 44, the arm is immediately swung downwardly as soon as the obstruction is passed to the point where pin 52 again engages lug 58. Spring 44 is strong enough so that the normal upward pressure of the ground against coulter disc 10 does not displace pin 52 from lug 58.

A second stop lug 60 extends from casting 18 in position to be encountered by pin 52 upon extreme upward swinging of arm 14. This limits the upward swinging of arm 14 if a very large obstruction is encountered so that spring 44 is not stressed beyond its elastic limit and thereby damaged; and the parts can be made of such strength that, in this event, the entire plow to which the coulter is atached will be lifted sufliciently to clear the obstruction.

Lubrication of sleeve 42 is accomplished through a grease fitting 62 of well known type which opens into a groove 64 in casting 18 outside of sleeve 42. Openings as 66 through sleeve 42 provide communication from groove 64 to the interior of sleeve 42 so as to apply the lubricant to the surface of pintle 40. In this way all of the bearing surfaces may be amply supplied with lubricant by the occasional application of a grease gun to fitting 62.

The operation of the device is thought to be clear from the foregoing description, sufficient to say, as the plow to which the device is attached moves down the field coulter disc 10 will trail behind journal portion 22 and swing slightly from side to side to align itself with the direction of movement. It will cut a slit in the soil to facilitate the action of the plow bottom and will be held at a predetermined depth by the force of spring 44 acting against pin 52 and maintaining the latter in contact with lug 58. If an obstruction is encountered, disc 10 may rise with upward swinging of arm 14 and additional flexing of spring 44; but as soon as the obstruction is passed, the spring will force arm 14 again downwardly and restore the parts to normal working position. If the obstruction is very large, excessive flexing of spring 44 is prevented by engagement of pin 52 with lug 60 whereupon, it the structure remains intact under such conditions, the whole plow will be raised.

A specific embodiment of the invention has been shown and described, but it is to be understood that variations of the invention may occur to those skilled in this art.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A coulter mounting comprising a support arranged to be carried by a plow structure and providing a substantially horizontally disposed bore arranged transversely of the direction of travel of the plow, a pintle rigidly supported in said support and disposed coaxially within said bore, a coulter arm structure including a sleeve journaled on said pintle and also journaled in said bore and extending outwardly of said support, a coulter arm fixed on said sleeve outwardly of said support and carrying a coulter secured to said arm at a point spaced from said sleeve, and means yielding urging said coulter arm in a downward swinging direction.

2. A coulter mounting having all the characteristics of claim 1 in which the yielding means comprises a spiral spring anchored to said pintle and engaged with said coulter arm structure.

3. A coulter mounting having all the characteristics of claim 2 and including stop means On said support and stop means on said arm structure engageable with the stop means on said support and positioned to limit the downward swinging movement of said arm structure when so engaged.

4. A coulter mounting having all the characteristics of claim 3 in which said stop means on said arm structure comprises a pin secured in said coulter arm spaced from said sleeve and in which said support has a shoulder in position to be engaged by said pin after a predetermined amount of downward swinging movement.

5. A coulter mounting having all the characteristicsof claim 2 in which said means for anchoring the spiral spring comprises a pin secured in said pintle transversely thereof and outwardly of said coulter arm structure.

6. A coulter mounting having all the characteristics of claim 2 in which the spiral spring is biased to swing said arm downwardly and also to urge said arm inwardly toward said support.

7. A coulter mounting having all th characteristics of claim 1 in which said support comprises a pivot element journaled for pivotal movement providing side-to-side swinging of said coulter arm structure.

8. A coulter mounting having all the characteristics of claim 3 in which said support also includes stop means engageable by the stop means on said arm structure and positioned to limit the upward swinging movement of said arm structure when so engaged.

References Cited UNITED STATES PATENTS 1/1966 Bayne 111-7 X 5/1967 Moran 111-7 

1. A COULTER MOUNTING COMPRISING A SUPPORT ARRANGED TO BE CARRIED BY A PLOW STRUCTURE AND PROVIDING A SUBSTANTIALLY HORIZONTALLY DISPOSED BORE ARRANGED TRANSVERSELY OF THE DIRECTION OF TRAVEL OF THE PLOW, A PINTLE RIGIDLY SUPPORTED IN SAID SUPPORT AND DISPOSED COAXIALLY WITHIN SAID BORE, A COULTER ARM STRUCTURE INCLUDING A SLEEVE JOURNALED ON SAID PINTLE AND ALSO JOURNALED IN SAID BORE AND EXTENDING OUTWARDLY OF SAID SUPPORT, A COULTER ARM FIXED ON SAID SLEEVE OUTWARDLY OF SAID SUPPORT AND CARRYING A COULTER SECURED TO SAID ARM AT A POINT SPACED FROM SAID SLEEVE, AND MEANS YIELDING URGING SAID COULTER ARM IN A DOWNWARDLY SWINGING DIRECTION. 